The present disclosure relates to an angular velocity sensor.
Recently, angular velocity sensors have been used in various applications, for example, in defense sector applications such as satellites, missiles, unmanned aircraft, or the like; in automobile applications such as air bags, electronic stability control (ESC), black boxes for vehicles, or the like; a hand shaking prevention applications of camcorders, motion sensor of mobile phones or game consoles, navigation applications, and the like.
An angular velocity sensor generally has a configuration in which a mass body is adhered to an elastic substrate such as a membrane, or the like, in order to measure angular velocity. Through the above-mentioned configuration, the angular velocity sensor may calculate angular velocity by measuring Coriolis force applied to the mass body.
In detail, a scheme of measuring angular velocity using an angular velocity sensor is as follows. First, the angular velocity may be calculated by Coriolis force “F=2mΩv”, where “F” is the Coriolis force acting on the mass body, “m” is a mass of the mass body, “Ω” is an angular velocity to be measured, and “v” is a motion velocity of the mass body. Among others, since the motion velocity v of the mass body and the mass m of the mass body are values known in advance, the angular velocity Ω may be calculated by sensing the Coriolis force (F) acting on the mass body.
Meanwhile, the angular velocity sensor according to the prior art includes a piezoelectric body or a piezo-resistor disposed on a membrane (a diaphragm) in order to drive a mass body or sense displacement of the mass body, as disclosed in the following Art Document (Patent Document 1: US20110146404 A1).